by Ken Johnson, Teledyne LeCroy, Chestnut Ridge, N.Y, How2Power Today, May 16 2017
Focus:
In most cases, optimal operation of a motor by a variable-frequency drive requires some
direct sensing of the motor operation (sensored) or control system calculation of these
quantities from other known data (sensorless). A motor running in a sensorless mode in
normal operation would likely still be instrumented during design testing, or instrumented
differently. This part 16 discusses the different parameters that are measured in motor
applications—namely torque, speed, and rotor shaft position—and describes operation of the
various types of analog and digital sensors used to measure these variables. Torque
sensors described include those with 0-xVdc, mV/V, and frequency modulated outputs. Analog
speed, direction and position sensors described include analog tachometers and resolvers.
Digital speed, direction, and position sensors include pulse tachometers, Hall effect
sensors, and quadrature encoder interfaces. Angle tracking observers and their use with
analog and digital encoders are also discussed. Measurements of various sensor outputs and
related calculations are demonstrated using Teledyne LeCroy’s Motor Drive Analyzer.
What you’ll learn:
View this Source (requires a PDF Viewer installed on your device)